Less than three months after racial friction led to student protests at George Washington University, the school has almost doubled the number of black students in the incoming freshman class.

The entering class of undergraduates at the private college in Northwest Washington is expected to include 74 blacks among 1,231 students, said university spokesman Dan Moshavi. That would make the class of 1991 6 percent black, up from the 3.4 percent black presence in last year's freshman class.

Most of the increased black enrollment results from an expanded recruiting program in Washington's high schools. GW has attracted seven of the District's top high school students, including both the valedictorian and salutatorian from Anacostia High School.

"We obviously want to increase minority enrollment," Moshavi said. "To a large extent, the reason we don't attract minority students is financial." Tuition and fees at GW are expected to run about $14,000 this year.

But black students who tell of isolation and outright harassment on campus argue that GW has found itself victim of a Catch-22: Admissions officers find it difficult to recruit blacks largely because there are so few blacks on campus.

In February, the members of an all-white fraternity, Delta Tau Delta, advertised a White History Week party during the observance of Black History Month. A revitalized campus Black People's Union demanded and got an apology. But the incident, and hate mail subsequently sent to the black group, led to calls for increased recruiting of blacks. Black students worked with admissions officers this spring, visiting high schools and college fairs.

The result is that GW, which had a black enrollment of 7 percent as little as three years ago, has reversed the dwindling black presence.

The bulk of the new enrollment comes from the District, where the university since 1969 has run the Educational Opportunity Program, a combination of financial aid and extra attention designed to ease the entry of black students into the overwhelmingly white campus. All but 17 of the blacks in the freshman class are from the District.

Among the District students entering GW this fall under the minority aid program are Narda Newby, valedictorian, All Saints High; Althea Evans, valedictorian, Anacostia High; Marsha Anderson, salutatorian, Anacostia High; Valerie Littlejohn, salutatorian, Eastern High; Yvonne Gray, salutatorian, Holy Spirit High; Julie Reed, salutatorian, McKinley High; and Sheila Coble, salutatorian, School Without Walls.